A proposed structure of a vehicle is equipped with an engine operated to output driving power and with a motor operated to output driving power. The start of the engine is controlled according to a target air outlet temperature of an air outlet of an air conditioning system provided in a passenger compartment and a cooling water temperature of the engine, on a start of the vehicle and during a low speed drive of the vehicle (see, for example, Japanese Patent Laid-Open No. H10-278569). The vehicle of this proposed structure refers to the target air outlet temperature and the cooling water temperature of the engine and determines the requirement for heating the passenger compartment in the low cooling water temperature condition. Upon the requirement for heating the passenger compartment, the engine is started even on the start of the vehicle or during the low-speed drive of the vehicle. The cooling water heated by the operation of the engine is used to heat the passenger compartment.